Let a stalled apt mirror fail the job rather than hold it

Both Linux test jobs on this branch sat an hour in apt-get, on runners
where the same step takes seconds, and a job with nothing to time it out
holds the pull request red-free and unfinished until the six hour limit.
Three retries and a twenty second timeout give apt another mirror, and
five minutes on the step gives the job an end.

.github/workflows/release.yml

@@ -46,9 +46,11 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.12"
-      - run: |
-          sudo apt-get update
-          sudo apt-get install --no-install-recommends -y \
+      - timeout-minutes: 5
+        run: |
+          apt="-o Acquire::Retries=3 -o Acquire::http::Timeout=20"
+          sudo apt-get $apt update
+          sudo apt-get $apt install --no-install-recommends -y \
             libegl1 libgl1 libxkbcommon0 libdbus-1-3 libglib2.0-0 \
             libfontconfig1 libfreetype6 libgssapi-krb5-2
       - run: python -m pip install --quiet PyQt6